June, 1940
NOTES
with a type K potentiometer and a copperconstantan thermocouple calibrated against a thermometer which had been calibrated by the Bureau of Standards. The molecular weights were determined by the vapor density method. The measured vapor pressures could all be represented by an equation of the conventional form: log p = A / T B . The values of the constants, the average deviation of the observed from the calculated vapor pressures and the values of certain derived quantities and of the molecular weights are given in the table.
+
Compd.. . . . . . . . . . . . . . . . P(CHs)$ As(CH3)a Sb(CHs)s A , . . . . . . . . . . . . . . . . . . . . -1518 -1456 -1697 B ..................... 7.7627 7.3936 7.7068 Av. dev., yo... . . . . . . . . . 1 1.5
